A water filter comprises a filter cylinder installed with a filter material and a filer casing screwed on the filter cylinder. Or a water filter is formed by a filter material installed in a sealed container. Water flows into the water filter from the filter casing or a water inlet of the sealed container, and flows through the filter material of the filter cylinder or the sealed container. Then water is drained out from a water outlet of the filter casing or the sealed container to be used. Both the water inlet and water outlet of the filter casing or the sealed container are installed separately in a joint for connecting with a water tube conveniently. Therefore, no matter a removable filer material of the filter cylinder or a non-removable filter material of the sealed container, the water inlet or water outlet is necessary to be installed. Besides, the joint is also necessary for the water inlet or water outlet in order to install a water tube conveniently.
Three ways are used in the prior art joint connecting with a water inlet or water outlet of a water filter, which are described as the followings.
Referring to FIGS. 1 and 2, the first prior art is a screw connection method in that a joint is connected with a water filter. The inner threads 100, 110 are separately formed on the inner diameters of a water inlet 10 or a water outlet 11 of filter casing 1 or a sealed container; and outer threads 20, 21 are formed on the outer sides of two axial ends of the front side and the back side of a joint 2, and then the back end of the joint 2 is screwed with a screw nut 22 by using the same thread pitch. Furthermore, the screw nut 22 is screwed with the outer thread 21. After the T shape sleeve 30 is assembled to a water tube 3 by a T shape sleeve 30 being inserted into one end of the water tube 3, a screwing effect of a screw nut 22 which is screwed into a joint 2 facilitates a water tube 3 to be assembled to the inner hole of the joint 2 so as to offer a function of connecting another water filter or water inlet and outlet. However, the traditional screw connection method has not only complicated components, but also has a disadvantage of increasing the manufacturing procedure. For more detail, because several layers of waterproof tapes 200, 210 must be covered on each outer thread of each screw connecting position, in order to increase the tightness between the inner thread and the outer thread, the manufacturing procedure becomes more complicated and requires much time and work. In addition, the T shape sleeve 30 installed into the water tube 3 may loose so as to induce a problem of leaking water. Thus, the manufacture cost cannot be reduced greatly, and in operation, the manufacture process is inconvenient and slow in assembly. In a further prior art, inner threads 100, 110 are separately formed on a water inlet 10 or a water outlet 11 of a filter casing 1 or a sealed container. The front and the external side of a joint 2 is formed with an outer thread 23, and the back side of the joint 2 is formed with a polygonal shape 24. By the same thread pitch and the same external diameter of an inner thread and an outer thread, a water inlet 10 and a water outlet 11 can be screwed into one end of the joint 2. Then a T shape sleeve 31 is assembled to the outer side of a water tube 3, and at the same time, a waterproof washer 4 is inserted into the inner hole of the joint 2. The front and the external side of the T shape sleeve 31 are formed with a plurality of tapered claws 310 and a plurality of slits 311 which are axially arranged, so that the front end of the T shape sleeve 31 is elastic to be inserted easily into the outer side of the water tube 3. Then the waterproof washer 4, the T shape sleeve 31 and the water tube 3 are inserted into the inner hole of the joint 2. Finally the raised claws 310 which are on the front and outer side of T shape sleeve 31 are wedged in the joint 2, so that the assembly of the water inlet 10 and water outlet 11 of the sealed container or the filter casing 1 with the water tube 3 is complete, as illustrated in FIGS. 3 and 4. Although the second prior art used in assembling a water tube may have an advantage of rapid assembly, the prior art still has several disadvantages. For more detail, because several layers of waterproof tapes 200, 210 must be covered on each outer thread of each screw connecting position, in order to increase the tightness between the inner thread and the outer thread, the manufacturing procedure becomes more complicated and requires much time and work. In addition, the polygonal shape 24 protrudes out of the the sealed container and the filter casing. As a result, it is easily damaged by collision.
In another prior art, a waterproof washer 4 is installed directly in a water inlet or water outlet of a filter cylinder or filter casing, then a sleeve 5 is pushed into the water inlet or water outlet of filter cylinder or filter casing in force. A C sharp clip is clipped on the round ring tube 5. A periphery of the C shape clip is formed with a plurality of metal elastomers 50. Because each metal elastmore 500 leans toward the same direction, the sleeve 5 can be pushed easily into the water inlet 10 or water outlet 11 of the filter cylinder or filter casing 1. A T shape sleeve 31 is sleeved on the outer side of the water tube 3. The T shape sleeve 31 has the same features of the structure as mentioned above. The front 1 outer wall of the T shape sleeve 31 has a plurality of axially arranged claws 311 and a plurality of slits 310. so that the front end of the T shape sleeve 31 is elastic and thus it can be inserted easily into the exterior of the water tube 3. Then the waterproof washer 4, the T shape sleeve 31 and the water tube 3 are inserted into the round ring tube 5. Finally, the claws are in the front end and exterior of T shape sleeve 31 are locked to the sleeve 5, so that the assembly of the water inlet 10 and water outlet 11 of the sealed container or the filter casing 1 with the water tube 3 is completed as illustrated in FIGS. 5 and 6. The method has a simple structure, but a plurality of metal elastomers 500 must be arranged on the sleeve 5. Besides, each metal elastomer leans toward the same direction in order to reach desirable goals. Otherwise, the water tube 3 is not possible to be installed into the water inlet 10 or water outlet 11 of the filter cylinder or filter casing 1. In addition, since the sleeve 5 must be pushed to enter into the water inlet 10 or water outlet 11 of the filter cylinder or filter casing 1 in force, the inner walls of the water inlet 10 or water outlet 11 of the filter cylinder or filter casing 1 are easily damaged for the sake of great pushing force. Meanwhile the damaged inner walls of the water inlet 10 or water outlet 11 of the filter cylinder or filter casing 1 will reduce the assembly of the water tube 3. Thus, it is happened that the sleeve 5 explodes s for the sake of high water pressure.
The present invention is modified for improving the disadvantages of the prior art water inlet or water outlet of the filter cylinder, which is based on the manufacture experiences of several decades to follow the principles of economy and efficiency. In assembly, the waterproof washer encloses a front end of the T shape sleeve, and then the T shape sleeve with the waterproof washer is placed into the polygonal hole from the round opening; and then the water tube is placed in T shape sleeve with a part of the water tube protruding out, and then the joint is installed into a water inlet or water outlet of a sealed container or filter casing. The joint used in one of a water inlet or water outlet of a filter cylinder has several advantages, such as convenient operation, quick combination and high pressure-tolerance.